Friedrich Wilhelm Nietzsche ( or 15 October 1844 – 25 August 1900) was a German philologist, philosopher, cultural critic, poet and composer. He wrote several critical texts on religion, morality, contemporary culture, philosophy and science, displaying a fondness for metaphor, irony and aphorism.
Nietzsche's key ideas include the Apollonian/Dionysian dichotomy, perspectivism, the Will to Power, the "death of God", the Übermensch and eternal recurrence. Central to his philosophy is the idea of "life-affirmation", which involves questioning of any doctrine that drains one's expansive energies, however socially prevalent those ideas might be. His radical questioning of the value and objectivity of truth has been the focus of extensive commentary and his influence remains substantial, particularly in the continental philosophical tradition comprising existentialism, postmodernism, and post-structuralism.